The present invention relates to a cable operated detoxification apparatus for rapid, in-place remediation of impounded chemical and low radioactive aqueous and sludge wastes as produced by sewage treatment plants or other industrial waste producing operations.
My prior U.S. Pat. Nos. 4,184,958, 4,079,003 and 4,028,240 relate to methods and apparatus comprised of a process tool which is repeatedly passed through a semi-liquid body of hazardous waste material while distributing a treatment chemical uniformly into the body of waste material. The process tool is pulled by a cable which traverses the body of hazardous material and extends between a pulling means on one side and an anchor means on the other side of the body of waste.
While the apparatus described and shown in my prior patents is useful for distributin gtreatment chemicals into a body of waste material, no means are disclosed therein for preventing the escape to atmosphere of noxious or toxic gases generated during the treatment process. Also, my prior device is limited to unidirectional distribution of chemicals where a supply of a single particular chemical to be distributed is piled in a location adjacent one end of the cable whereby the process tool is able to scoop up a supply of chemical to be distributed from the pile at one end of its pass through the waste. By the time the process tool has reached the other end of its pass, there may be too much or too little of the treatment chemical left in the process tool for effective treatment.
It is accordingly an object of the invention to provide an improved apparatus capable of bi-directionally distributing one or more of a mixture of selected treatment chemicals from storage supplies thereof at rates dependent on the conditions encountered at the job site and, if necessary, in a manner which does not result in the release of toxic or harmful gases to the atmosphere.
When a chemical treatment agent such as calcium oxide is added to aqueous sludge an exothermic reaction results creating high temperatures sufficient to kill bacteria and the resultant odors caused thereby during dehydration of the sludge. The resulting reaction product comprises a hard friable material substantially free or odor, and which has toxic metals locked therein in an insoluble form. As the process tool is pulled through the lagoon, an accurate determination of the mixing effectiveness or degree of treatment can be made by sensing the tension in the pulling cable which increases as the reaction takes place and the sludge hardens so that the cable tension can be used to control the amount of chemicals to be added to the sludge.